Foldable stroller

ABSTRACT

A stroller includes laterally spaced apart hubs that interconnect upper, middle and front frame member assemblies of a chassis of the stroller. The hubs are disposed one each along opposite sides of the stroller, and include mounting structures for coupling two or more of the strollers together in a side-by-side fashion. The hubs further include other mounting structures for mounting a seat assembly to the stroller chassis and for supporting both rearward facing and frontward facing orientation of the seat assembly as well as selectable inclination positions. Each of the hubs includes a folding mechanism for supporting folding of the stroller, such as for transport in a vehicle or for storage. Other laterally spaced apart hubs are provided along the upper frame members for providing a second point of attachment between two coupled strollers and for mounting of accessories.

This application is a continuation of U.S. patent application Ser. No.13/201,412 filed on Aug. 12, 2011, which is a National Phase Applicationof PCT/CA2010/000199 filed on Feb. 12, 2010, which claims the benefitunder 35 U.S.C. 119(e) of U.S. Provisional Patent Application No.61/152,078 filed on Feb. 12, 2009. The instant application incorporatesby reference U.S. patent application Ser. No. 13/201,412, in itsentirety.

FIELD OF THE INVENTION

The instant invention relates generally to foldable strollers, and moreparticularly to foldable strollers that may be used separately totransport a single occupant, or that may be coupled together totransport multiple occupants.

BACKGROUND OF THE INVENTION

Families with small children tend to acquire a wide variety ofspecialized equipment for transporting their children from place toplace. In particular, car seats are required for transporting childrenin vehicles over long distances or during inclement weather, andstrollers are required for transporting children locally over shorterdistances. Often, a stroller is carried to a destination in the back ofa vehicle. Upon arriving at the destination, the children aretransferred out of the vehicle and into the stroller. It is thereforecommon that strollers are designed to be collapsible or foldable so asto fit easily within the trunk of a vehicle, or for transport on publictransit or aircraft, etc.

Multiple-child strollers, such as for instance double or triplestrollers, are known for transporting more than one child at a time. Onetype of multiple-child stroller provides two or more seating areas in apermanent side-by-side or tandem arrangement. Of course, such strollersdo not permit children to be moved along separate paths and cannot beseparated if only single child transport is desired. In view of theselimitations, a family often resorts to purchasing a multiple-childstroller for transporting more than one child at a time, as well as asingle stroller for those times when only single child transport isdesired. Such families not only incur additional expense, but must alsostore a plurality of strollers and must dispose of the multiple-childstroller, and then eventually the single stroller, as the children age.

Another type of multiple-child stroller is based on separable,individual strollers that can be coupled together to form a side-by-sideunit, and that can be decoupled when single child transport is desired.Examples of such tandem coupling approaches are disclosed in U.S. Pat.Pub. No. 2008/0179863 to Schonfeld, U.S. Pat. No. 4,805,938 to Redmondet al. and U.S. Pat. No. 5,522,121 to Fraynd et al. These couplingsystems for joining two strollers have used elongated releasable clampsor other elongated connectors to couple the strollers. The resultingwidth of such designs generally is greater than standard door widths,limiting the utility thereof. Moreover, the clamping devices are bulkyand not conveniently stored during separate operation of the strollers,and/or separate storage of detached wheels is required when thestrollers are operated in a coupled-together mode. In addition, thesystem that is disclosed by Schonfeld requires the rear wheels of eachstroller to be spaced relatively closely together, so that when theindividual strollers are coupled together the inside rear wheel of onestroller does not interfere with the inside rear wheel of the otherstroller. Although the strollers are likely to be stable when coupledtogether, they are also likely to be far less stable, and thereforesubject to tipping, when used separately. In particular, the relativelyclosely spaced rear wheels of the stroller are located below the centerof weight of the child and close to the handle. The front strollerwheels, which are more widely spaced apart than the rear wheels, are notlikely to provide sufficient stabilization when the stroller is beingpushed over uneven or soft ground surfaces, since the front wheels of astroller often come out of contact with the ground surface under theseconditions.

UK Patent Application GB 2,413,311 to Naseby describes a system wherebytwo strollers may be closely coupled together to form a side-by-sidedouble stroller. In particular, the front and rear wheels and the handlealong one side of a first stroller are removed, and the resultingexposed stubs are inserted into corresponding brackets along one side ofa second stroller, so as to couple the two strollers together. Althoughthis system reduces the overall width of the coupled strollers comparedto the above-mentioned systems, it also requires separate storage ofdetached parts and the coupling/decoupling procedure is awkward. Thestroller that is disclosed by Naseby is better suited to being usedeither as a single stroller or as a double stroller for prolongedperiods of time, since rapid conversion between coupled and decoupledconditions is hindered by the need to remove, store and reattachmultiple stroller parts.

UK Patent Application GB 2,373,484 to Sear et al. discloses yet anothersystem whereby two strollers may be closely coupled together to form aside-by-side double stroller. In particular, to connect two strollerstogether one side of each stroller is equipped with a rail extendingfrom the front to the rear of the stroller. The shapes of the respectiverails are such that one rail mates and interlocks with the other rail.To attach the two strollers together requires the user to unlock thefront and rear wheels of one of the strollers, retract them and lockthem in the retracted position, to align the rails of each stroller, andthen to hold one stroller still whilst pushing the other strollerbackwards until the two are locked together. In addition to beingawkward to use, the rails extending from the front to the rear of thestroller prevent the stroller from being folded for storage ortransport. Further, the rail system employed by Sear et al. is prone tofouling by pebbles, sand and other debris that may be kicked up into therails due to their close proximity to the wheels and ground surface.

Of course, in addition to simply providing a suitable structure forcoupling two strollers together, it is also necessary to consider avariety of other factors relating to safety and convenience of use. Inparticular, prior art brake systems for strollers may prove to beinadequate or unworkable when two individual strollers are coupledtogether to form a unitary structure. For instance, removing orrelocating parts of the strollers in order to couple them together mayprevent a prior art brake system from operating properly. In addition,the brake mechanism of either stroller should be sufficiently strong toprevent both strollers from moving when coupled together, and shouldengage reliably.

Another notable shortcoming of the prior art multi-child strollers isthe lack of adaptable seating systems. In particular, the prior artstrollers provide two seats that are suitable for toddler age children,but lack suitable seating to accommodate newborn children andpre-toddlers. Thus, families with a toddler and a newborn may still needto purchase a separate stroller in order to safely accommodate thenewborn. Of course, even when both children can be accommodated in oneof the prior art multi-child strollers, still the ability to adjust theorientation and/or the inclination of the seats is limited.

It would be advantageous to provide a stroller system that overcomes atleast some of the above-mentioned limitations of the prior art.

SUMMARY OF EMBODIMENTS OF THE INVENTION

In accordance with an aspect of an embodiment of the invention there isprovided a foldable stroller, comprising: left and right front wheels;left and right side laterally spaced-apart front frame members, each ofthe left and right side front frame members having a forward end portionand a rearward end portion, the forward end portion of the left sidefront frame member being coupled to the left front wheel and the forwardend portion of the right side front frame member being coupled to theright front wheel, the left and right side front frame members beingrotatable as a unit; left and right rear wheels; left and right sidelaterally spaced-apart middle frame members, each of the left and rightside middle frame members having a forward end portion and a rearwardend portion, the rearward end portion of the left side middle framemember being coupled to the left rear wheel and the rearward end portionof the right side middle frame member being coupled to the right rearwheel, the left and right side middle frame members being rotatable as aunit; left and right side laterally spaced-apart upper frame members,each of the left and right side upper frame members having a forward endportion and a rearward end portion, the left and right side upper framemembers being rotatable as a unit; and, left and right side laterallyspaced apart folding assemblies each comprising a housing supported bythe forward end portion of a corresponding one of the left and rightmiddle frame members, each of the left and right side folding assemblieshaving disposed within the housing a first rotatable member and a secondrotatable member rotatably coupled to a pivot member for rotation abouta common axis of rotation, the first rotatable member and the secondrotatable member coupled together via a linkage assembly comprising afirst linkage arm having a first end pivotally attached to the firstrotatable member and a second linkage arm having a first end pivotallyattached to the second rotatable member, the linkage assembly furthercomprising a linkage pin linking together a second end of the firstlinkage arm that is opposite the first end thereof and a second end ofthe second linkage arm that is opposite the first end thereof, thehousing of each folding assembly having an inner surface defining aguide-channel that extends generally from an edge portion of the housingalong a direction toward the pivot member, the linkage pin projectinginto the guide channel and being slidingly retained therein, therearward end portion of a corresponding one of the left and right frontframe members being attached to one of the first and second rotatablemembers and the forward end portion of a corresponding one of the leftand right upper frame members being attached to the other one of thefirst and second rotatable members, wherein the linkage pin slidinglytravels within the guide-channel such that the first rotatable memberand the second rotatable member rotate relative to each other in asynchronized fashion when the foldable stroller is converted between arolling configuration and a folded configuration.

In accordance with an aspect of an embodiment of the invention there isprovided a folding assembly for a stroller frame having a front framemember, a middle frame member and an upper frame member, comprising: apivot member; a first rotatable member; a second rotatable member, thefirst and second rotatable members being rotationally coupled to thepivot member to rotate about a common axis of rotation; a linkageassembly comprising a first linkage arm having a first end pivotallyattached to the first rotatable member and a second linkage arm having afirst end pivotally attached to the second rotatable member, the linkageassembly further comprising a linkage pin connecting together a secondend of the first linkage arm that is opposite the first end thereof anda second end of the second linkage arm that is opposite the first endthereof; and, a housing for containing the pivot member, the first andsecond rotatable members, and the linkage assembly, the housing havingan inner surface defining a guide-channel that extends generally from anedge portion of the housing along a direction toward the pivot member,the linkage pin projecting into the guide-channel and being slidinglyretained therein, wherein the linkage pin slidingly travels within theguide-channel for guiding the first rotatable member and the secondrotatable member to rotate relative to each other in a synchronizedfashion.

In accordance with an aspect of an embodiment of the invention there isprovided a folding mechanism usable with a foldable stroller havingfront, middle and upper frame members, the folding mechanism comprising:first and second rotatable members rotatably mounted to rotate relativeto each other, the first rotatable member being disposed for rotation ina first rotation plane and the second rotatable member being disposedfor rotation in a second rotation plane that is spaced apart from andsubstantially parallel to the first rotation plane; a linkage assemblycomprising a first linkage arm having a first end pivotally attached tothe first rotatable member and a second linkage arm having a first endpivotally attached to the second rotatable member, the linkage assemblyfurther comprising a linkage pin connecting together a second end of thefirst linkage arm that is opposite the first end thereof and a secondend of the second linkage arm that is opposite the first end thereof;and, a housing for containing the first and second rotatable members andthe linkage assembly, the housing having at least one inner surfacewithin which a guide-channel is defined, the linkage pin projecting intothe guide-channel and being slidingly retained therein, wherein theguide-channel is oriented for guiding the linkage pin along apredetermined direction of travel when the folding mechanism is actuatedbetween a folded configuration of the foldable stroller and an unfoldedconfiguration of the foldable stroller, so that the first rotatablemember and the second rotatable member are constrained to rotaterelative to each other in a synchronized fashion.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: left and right front wheels; left andright side laterally spaced-apart front frame members, each of the leftand right side front frame members having a forward end portion and arearward end portion, the forward end portion of the left side frontframe member being coupled to the left front wheel and the forward endportion of the right side front frame member being coupled to the rightfront wheel; left and right rear wheels; left and right side laterallyspaced-apart middle frame members, each of the left and right sidemiddle frame members having a forward end portion and a rearward endportion, the rearward end portion of the left side middle frame memberincluding a wheel mounting structure along an outer face thereof andalong an inner face thereof opposite the outer face, the rearward endportion of the right side middle frame member including a wheel mountingstructure along an outer face thereof and along a inner face thereofopposite the outer face, so that the left rear wheel is selectablymountable adjacent to either the outer face or the inner face of theleft side middle frame member, and so that the right rear wheel isselectably mountable adjacent to either the outer face or the inner faceof the right side middle frame member; left and right side laterallyspaced-apart upper frame members, each of the left and right side upperframe members having a forward end portion and a rearward end portion;and, left and right side laterally spaced apart hubs disposed betweenand interconnecting corresponding ones of the front, middle and upperframe members, the left and right side hubs having complementary halvesof an interlocking mounting structure defined on outward facing surfacesthereof, wherein side-by-side coupling of two strollers is supported byinterlocking one of the left and right side hubs of one of the twostrollers with the other one of the left and right side hubs of theother one of the two strollers.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: a front frame member assemblysupporting a pair of laterally spaced apart front wheels; a middle framemember assembly supporting a pair of laterally spaced apart rear wheels,the middle frame member assembly configured so that the rear wheels aredetachably mountable one each adjacent to outer faces of the middleframe member assembly for operation in a detached operating conditionbetween a first and a second stroller, and so that the rear wheels aredetachably mountable one each adjacent to inner faces of the middleframe member assembly for operation in a coupled operating conditionbetween a first and a second stroller; an upper frame member assemblywith a push handle portion; first and second laterally spaced apart hubsdisposed between and interconnecting the front frame member assembly,the middle frame member assembly, and the upper frame member assembly,the first hub having a first mounting structure defined on an outwardfacing surface thereof and the second hub having a second mountingstructure defined on an outward facing surface thereof, the secondmounting structure different than the first mounting structure, thefirst and second mounting structures defining complementary halves of afirst interlocking coupling mechanism; wherein the first mountingstructure disposed on the outward facing surface of the first hub of thefirst stroller is aligned with and engages the second mounting structureon the outward facing surface of the second hub of the second stroller,for detachably securing the first stroller to the second stroller in aside-by-side fashion.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: a front frame member assemblysupporting a pair of laterally spaced apart front wheels; a middle framemember assembly supporting a pair of laterally spaced apart rear wheels,the middle frame member assembly including first and second wheelmounting structures disposed along outer faces thereof on opposite sidesof the stroller and including third and fourth wheel mounting structuresdisposed along inner faces thereof on opposite sides of the stroller, sothat the pair of rear wheels is selectably mountable adjacent to eitherthe outer faces or the inner faces of the middle frame member, a lateralseparation between the pair of rear wheels being greater when the pairof rear wheels is mounted adjacent to the outer faces of the middleframe member relative to when the pair of rear wheels is mountedadjacent to the inner faces of the middle frame member; an upper framemember assembly extending to a push handle end; a first hub disposed ona first side of the stroller and a second hub disposed on a second sideof the stroller and opposite the first hub, the first and second hubsdisposed between and interconnecting the front frame member assembly,the middle frame member assembly, and the upper frame member assembly,the first hub having a raised flange portion of a first interlockingcoupling mechanism defined on an outward facing surface thereof and thesecond hub having a recessed slot portion of the first interlockingcoupling mechanism defined on an outward facing surface thereof; a thirdhub disposed on the first side of the stroller and proximate the pushhandle end of the upper frame member assembly and a fourth hub disposedon the second side of the stroller and proximate the push handle end ofthe upper frame member assembly, the third hub having one of a raisedflange portion and a recessed slot portion of a second interlockingcoupling mechanism defined on an outward facing surface thereof and thefourth hub having the other one of the raised flange portion and therecessed slot portion of the second interlocking coupling mechanismdefined on an outward facing surface thereof; wherein for coupling thestroller with a second stroller, the raised flange portion of the firsthub on the first side of the stroller slidingly engages the recessedslot portion of the second hub on the second side of the secondstroller, and the one of the raised flange portion and the recessed slotportion of the third hub on the first side of the stroller slidingengages the other one of the raised flange portion and the recessed slotportion on the fourth hub on the second side of the second stroller.

In accordance with an aspect of an embodiment of the invention there isprovided a method comprising: providing a first stroller and a secondstroller each comprising a frame supported by a pair of laterally spacedapart front wheels and a pair of laterally spaced apart rear wheels, theframe of each stroller comprising first and second mounting structureson a first side thereof and comprising third and fourth mountingstructures on a second side thereof, the second side opposite the firstside of the stroller, a maximum frame width being defined betweenoutward facing surfaces of the first and third mounting structures, eachone of the pair of laterally spaced apart rear wheels being detachablymounted adjacent to an outer face of a rear-wheel support member onopposite sides of the frame, such that a lateral separation between therear wheels is greater than the maximum frame width; detaching each rearwheel from a respective rear-wheel support member on each one of thefirst stroller and the second stroller; detachably mounting each rearwheel to an inner face of a respective rear-wheel support member onopposite sides of the frame of each one of the first stroller and thesecond stroller, such that for each one of the first stroller and thesecond stroller the rear wheels are laterally spaced apart by an amountthat is less than the maximum frame width of the respective stroller;and, detachably engaging the first and second mounting structures on thefirst side of the frame of the first stroller with the third and fourthmounting structures on the second side of the frame of the secondstroller, respectively, so as to couple the first stroller with thesecond stroller in a side-by-side fashion with two points of attachment,wherein a maximum overall width of the first and second stroller, whencoupled together in the side-by-side fashion, does not exceed the sum ofthe maximum frame width of the first stroller and the maximum framewidth of the second stroller.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: a rear wheel having a toothed hubdefining a plurality of retaining grooves arranged around acircumferential direction thereof; a stroller chassis with a rear-wheelsupport member having a wheel-mounting structure disposed along both aninner face and an outer face thereof, so that the rear wheel isselectably mountable adjacent to either the inner face or the outer faceof the rear-wheel support member, the toothed hub facing toward therear-wheel support member when the rear wheel is mounted thereto, andthe rear-wheel support member having a through-slot proximate thewheel-mounting structures; and, a brake device, comprising: a rocker armhaving a first end and a second end and being pivotally mounted adjacentto one of the inner and outer faces of the rear-wheel support member andproximate to the wheel-mounting structures; a control cable having acontrolling end and a pulling end, the pulling end being coupled to thefirst end of the rocker arm; and, an elongated linear-actuator assemblyhaving a first end that is pivotally coupled to the second end of therocker arm and having a second end opposite the first end, the secondend comprising a lock-pin support member and a lock-pin that is mountedperpendicular to the lock-pin support member and that extends in firstand second opposite directions from the lock-pin support member, one endof the lock-pin extending along the first direction through thethrough-slot in the rear-wheel support member for engaging one of theretaining grooves when the rear wheel and the rocker arm are mountedadjacent to different ones of the inner and outer faces of therear-wheel support member, and the other end of the lock-pin extendingalong the second direction for engaging one of the retaining grooveswhen the rear wheel and the rocker arm are mounted adjacent to the sameone of the inner and outer faces of the rear-wheel support member.

In accordance with an aspect of an embodiment of the invention there isprovided a brake device for a stroller, comprising: a rocker arm havinga first end and a second end and supporting a pivoting movement about apivot point that is defined between the first end and the second end; acontrol cable having a controlling end and a pulling end, the pullingend being coupled to the first end of the rocker arm; and, an elongatedlinear-actuator assembly having an overall length and comprising: aretaining rod having a length that is less than the overall length ofthe elongated linear-actuator assembly, the retaining rod having a firstend that is pivotally coupled to the second end of the rocker arm andhaving a second end with a flange extending perpendicularly from theretaining rod; a lock-pin support member having a first end and a secondend that is opposite the first end, the lock-pin support member having apassageway extending therethrough between the first and second ends, afirst portion of the passageway that is proximate the first end beingdimensioned smaller than the retaining rod flange, and a second portionof the passageway that is proximate the second end being dimensionedlarger than the retaining rod flange, a transition between the firstportion of the passageway and the second portion of the passagewaydefining an interior bearing surface, and the second end of theretaining rod being disposed within the second portion of thepassageway, when in an assembled condition, so that the retaining rodflange faces the interior bearing surface; a lock-pin for engaging aretaining groove of a rear wheel of the stroller, the lock-pin mountedperpendicularly to the lock-pin support member and proximate the secondend thereof, the lock-pin extending in first and second oppositedirections from the lock-pin support member; and first and secondresilient members disposed between the first end of the retaining rodand the first end of the lock-pin support member, the second resilientmember for driving the lock-pin into an engaged position when thecontrol cable acts to pull the rocker arm into a braking position andthereby compress the first resilient member, and the first resilientmember for retracting the lock-pin from the engaged position when thecontrol cable acts to release the rocker arm from the braking position,wherein the lock-pin engages one of the retaining grooves of the rearwheel of the stroller when in the engaged position, the rear wheel beingselectably mounted along either the first or second direction relativeto the elongated linear-actuator assembly.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: a rear wheel having a toothed hubdefining a plurality of retaining grooves arranged around acircumferential direction thereof; a stroller chassis with a rear-wheelsupport member having a wheel-mounting structure disposed along both aninner face and an outer face thereof, so that the rear wheel isselectably mountable adjacent to either the inner face or the outer faceof the rear-wheel support member, the toothed hub facing toward therear-wheel support member when the rear wheel is mounted thereto, andthe rear-wheel support member having a through-slot proximate thewheel-mounting structures; and, a brake system comprising a brakecontroller and a brake mechanism that is mounted adjacent to one of theinner face and the outer face of the rear-wheel support and proximate tothe wheel-mounting structures, the brake controller in communicationwith the brake mechanism via a control cable, the brake controller foractuating the brake mechanism between a braking condition and anon-braking condition, the brake mechanism comprising at least onecompression spring, a lock-pin support member and a retaining memberresponsive to the brake controller for retaining the lock-pin supportmember when in the non-braking condition and for releasing the lock-pinsupport member when in the braking condition, the brake mechanismfurther comprising a lock-pin mounted perpendicular to the lock-pinsupport member and having a first end extending away from the lock-pinsupport member in first direction and having a second end extending awayfrom the lock-pin support member in a second direction that is oppositethe first direction, the first end of the lock-pin extending through andprotruding beyond the through-slot in the rear-wheel support member,wherein when the retaining member releases the lock-pin support memberthe at least one compression spring pushes the lock-pin support memberso as to engage one end of the lock-pin in a retaining groove betweentwo adjacent teeth of the toothed hub, and wherein the first end of thelock-pin engages in the retaining groove when the rear wheel and thebrake mechanism are mounted to different ones of the outer face and theinner face of the rear-wheel support member, and wherein the second endof the lock-pin engages in the retaining groove when the rear wheel andthe brake mechanism are both mounted to a same one of the outer face andthe inner face of the rear-wheel support member.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: a front frame member assemblysupporting a pair of laterally spaced apart front wheels; a middle framemember assembly supporting a pair of laterally spaced apart rear wheels;an upper frame member assembly with a push handle portion; first andsecond laterally spaced apart hubs disposed between and interconnectingthe front frame member assembly, the middle frame member assembly, andthe upper frame member assembly, the first hub having a first mountingstructure projecting from an inward facing surface thereof and thesecond hub having a second mounting structure projecting from an inwardfacing surface thereof, the first mounting structure comprising a firstshaft extending from the first hub and the second mounting structurecomprising a second shaft extending from the second hub, the first andsecond shafts being axially aligned one with the other, each one of thefirst and second shafts having two mutually parallel flat sides and twoconvexly curved sides joining the two mutually parallel flat sides, thetwo mutually parallel flat sides being separated by a first distance;and, a seat assembly comprising at least one seat frame member and firstand second connector assemblies disposed one each on opposite sides ofthe at least one seat frame member, the first and second connectorassemblies each comprising a mounting surface having a recessed slotdefined therein, each recessed slot having a narrow portion disposedbetween two relatively wider portions, the narrow portion correspondingapproximately to the first distance between the two mutually parallelsides of each of the first and second shafts, wherein the narrow portionof the recessed slot of one of the first and second connector assembliesis aligned with the two mutually parallel sides of one of the first andsecond shafts, and the narrow portion of the recessed slot of the otherone of the first and second connector assemblies is aligned with the twomutually parallel sides of the other one of the first and second shafts,and thereafter the first and second shafts are urged from one of the tworelatively wider portions of the respective recessed slot, through thenarrow portion and into the other one of the two relatively widerportions for detachably mounting the seat assembly to the first andsecond hubs.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: a stroller chassis, comprising: a frontframe member assembly supporting a pair of laterally spaced apart frontwheels; a middle frame member assembly supporting a pair of laterallyspaced apart rear wheels; an upper frame member assembly with a pushhandle portion; and, first and second laterally spaced apart mountingstructures, the first mounting structure comprising a first shaft andthe second mounting structure comprising a second shaft, the first andsecond shafts being axially aligned one with the other, the perimeter ofeach of the first and second shafts, in a cross-section that is taken ina plane transverse to a respective length thereof, comprising twomutually parallel flat sides and two convexly curved sides joining thetwo mutually parallel flat sides; and, a seat assembly comprising atleast one seat frame member and third and fourth mounting structuresdisposed one each on opposite sides of the at least one seat framemember, each one of the third and fourth mounting structures comprisinga mounting surface having a recessed slot defined therein, the recessedslot being shaped with a narrow middle portion having a widthcorresponding substantially to a distance between the two mutuallyparallel flat sides of a respective one of the first and second shafts,and having a relatively wider end portion disposed one each on oppositesides of the middle portion, wherein the two mutually parallel sides ofeach of the first and second shafts are aligned with the narrow portionof a respective one of the recessed slots, and thereafter the first andsecond shafts are urged through the narrow portion from one of therelatively wider end portions to the other of the relatively wider endportions of the respective recessed slot, for detachably mounting theseat assembly to the stroller chassis.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: a stroller chassis, comprising: a frontframe member assembly supporting a pair of laterally spaced apart frontwheels; a middle frame member assembly supporting a pair of laterallyspaced apart rear wheels; an upper frame member assembly with a pushhandle portion; and, first and second laterally spaced apart hubsdisposed between and interconnecting the front frame member assembly,the middle frame member assembly, and the upper frame member assembly,the first hub having an inwardly facing surface with a raised peripheralportion defining a first rack comprising a first plurality of retaininggrooves in a side-by-side arrangement and the second hub having aninwardly facing surface with a raised peripheral portion defining asecond rack comprising a second plurality of retaining grooves in aside-by-side arrangement; and, a seat assembly comprising: at least oneseat frame member; first and second connector assemblies disposed oneeach on opposite sides of the at least one seat frame member fordetachably mounting the seat assembly to the first and second hubs ofthe stroller chassis, respectively, the first connector assembly havinga first pawl that is normally biased for selectably engaging at a time aportion of the first plurality of retaining grooves of the first rackand the second connector assembly having a second pawl that is normallybiased for selectably engaging at the time a corresponding portion ofthe second plurality of retaining grooves of the second rack; and, firstand second control cables each having a controlling end and a pullingend, the pulling end of the first control cable being in communicationwith the first pawl for controllably moving the first pawl between thenormally biased position and a retracted position in which the firstpawl is withdrawn from the first plurality of retaining grooves of thefirst rack, and the pulling end of the second control cable being incommunication with the second pawl for controllably moving the secondpawl between the normally biased position and a retracted position inwhich the second pawl is withdrawn from the second plurality ofretaining grooves of the second rack, wherein when the first pawl andthe second pawl are in the respective retracted positions, the firstpawl is movable past the first plurality of retaining grooves of thefirst rack and the second pawl is movable past the second plurality ofretaining grooves of the second rack for adjusting an inclination of theseat assembly relative to the stroller chassis.

In accordance with an aspect of an embodiment of the invention there isprovided a stroller, comprising: a stroller chassis comprising a frontframe member assembly, a middle frame member assembly, and an upperframe member assembly; first and second laterally spaced-apart mountingmembers that are disposed between and that couple together the front,middle and upper frame member assemblies, each mounting membercomprising a plurality of retaining grooves that are arranged along anarcuate path and in a side-by-side fashion on inwardly facing surfacesof each of the first and second mounting members; and, a seat assemblycomprising at least one seat frame member and third and fourth laterallyspaced-apart mounting members disposed one each on opposite sides of theat least one seat fame member, the first mounting member and one of thethird and fourth mounting members being coupled together and supportingrotation therebetween when the stroller is in an assembled condition andthe second mounting member and the other one of the third and fourthmounting members being coupled together and supporting rotationtherebetween when the stroller is in the assembled condition, the thirdand fourth mounting members each comprising a controllably retractablepawl for selectably engaging a portion of the plurality of retaininggrooves on one of the first and second mounting members, for retainingthe seat assembly in a selected inclination orientation relative to thestroller chassis.

In accordance with an aspect of an embodiment of the invention there isprovided a system for mounting an accessory to a stroller, comprising: ahub disposed along a lateral frame member of the stroller and having afirst mounting structure defined on an outward facing surface thereof;and, an accessory having a second mounting structure defined on asurface thereof, the second mounting structure different than the firstmounting structure, the first and second mounting structures definingcomplementary halves of an interlocking coupling mechanism; wherein thefirst mounting structure disposed on the outward facing surface of thehub is aligned with and engages the second mounting structure on thesurface of the accessory for detachably mounting the accessory to thestroller.

In accordance with an aspect of an embodiment of the invention there isprovided a system for mounting an accessory to a stroller, comprising: ahub disposed along a lateral frame member of the stroller and having oneof a raised flange portion and a recessed slot portion of a firstinterlocking coupling mechanism defined on an outward facing surfacethereof; and, an accessory having the other one of the raised flangeportion and the recessed slot portion of the first interlocking couplingmechanism defined on a surface thereof, wherein for detachably mountingthe accessory to the stroller the one of the raised flange portion andthe recessed slot portion of the first hub engages the other one of theraised flange portion and the recessed slot portion on the accessory ina mutually interlocking fashion.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will now be described inconjunction with the following drawings, in which:

FIG. 1 a is a perspective view of a stroller according to an embodimentof the instant invention, with the seat web material omitted forclarity;

FIG. 1 b is a perspective view of the stroller of FIG. 1 a with the seatweb material illustrated;

FIG. 1 c is a perspective view of the stroller of FIG. 1 a, showing therear wheels mounted to the outer faces of the left side and right sidemiddle frame members;

FIG. 1 d is a perspective view of the stroller of FIG. 1 a, showing theright rear wheel mounted to the outer face of the right side middleframe member, and showing the left rear wheel detached from the leftside middle frame member;

FIG. 1 e is a perspective view of the stroller of FIG. 1 a, showing theleft rear wheel mounted to the inner face of the left side middle framemember, and showing the right rear wheel mounted to the outer face ofthe right side middle frame member;

FIG. 2 a is an enlarged view showing the upper left and upper right hubsof the stroller of FIG. 1 a;

FIG. 2 b is an enlarged view showing the lower left and lower right hubsof the stroller of FIG. 1 a;

FIG. 2 c shows the upper hubs of two strollers in a coupled condition;

FIG. 3 is a rear view showing first and second strollers in a coupledcondition, according to an embodiment of the instant invention;

FIG. 4 a shows an enlarged partial detail view of the brake mechanism ofthe stroller of FIG. 1 a;

FIG. 4 b shows a further enlarged partial detail view of the brakemechanism of the stroller of FIG. 1 a;

FIG. 4 c is a rear perspective view of the stroller of FIG. 1 a, showingthe brake lever and cable system;

FIG. 4 d shows an enlarged partial detail view of the brake lever thatis mounted on an upper hub of the stroller of FIG. 1 a;

FIG. 5 a is a partial side view showing the lower left hub interiormechanism detail of the stroller of FIG. 1 a, when in a rolling orunfolded configuration;

FIG. 5 b shows the detail within the dotted square area of FIG. 5 a;

FIG. 5 c shows the lower left hub interior mechanism of the stroller ofFIG. 1 a in a folded configuration;

FIG. 6 a is a side view of the stroller chassis of FIG. 1 a in a rollingconfiguration;

FIG. 6 b is a side view of the stroller chassis of FIG. 1 a in apartially-folded configuration;

FIG. 6 c is a side view the stroller chassis of FIG. 1 a in afully-folded configuration;

FIG. 7 a shows the seat mounting structure of the stroller of FIG. 1 aadjacent to a detachable, foldable toddler seat assembly;

FIG. 7 b shows a plan view of the mounting structure on the innersurface of the seat assembly coupling assembly;

FIG. 7 c shows a side view of the seat mounting structure on the centralhub of the stroller of FIG. 1 a;

FIG. 7 d shows a rear view of the mounting structure on the innersurface of the central hub of the stroller of FIG. 1 a;

FIG. 7 e shows a top view of the mounting structure on the inner surfaceof the central hub of the stroller of FIG. 1 a;

FIG. 8 a shows the seat reclining mechanism of the stroller of FIG. 1 ain a locked configuration;

FIG. 8 b shows the seat reclining mechanism of the stroller of FIG. 1 ain an unlocked configuration;

FIG. 9 a shows the child seat frame of the stroller of FIG. 1 a in anupright seat position;

FIG. 9 b shows the child seat frame of the stroller of FIG. 1 a in anormal seat position;

FIG. 9 c shows the child seat frame of the stroller of FIG. 1 a in areclined seat position;

FIG. 9 d shows the seat reclining mechanism when the seat frame of thestroller of FIG. 1 a is in the upright seat position;

FIG. 9 e shows the seat reclining mechanism when the seat frame of thestroller of FIG. 1 a in the normal seat position;

FIG. 9 f shows the seat reclining mechanism when the seat frame of thestroller of FIG. 1 a in the reclined seat position;

FIG. 10 shows a cup holder accessory adjacent the upper right hub of thestroller of FIG. 1 a; and,

FIG. 11 shows a tray accessory mounted on the stroller of FIG. 1 a.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The following description is presented to enable a person skilled in theart to make and use the invention, and is provided in the context of aparticular application and its requirements. Various modifications tothe disclosed embodiments will be readily apparent to those skilled inthe art, and the general principles defined herein may be applied toother embodiments and applications without departing from the scope ofthe invention. Thus, the present invention is not intended to be limitedto the embodiments disclosed, but is to be accorded the widest scopeconsistent with the principles and features disclosed herein.

Referring to FIG. 1 a, shown is a perspective view of a stroller 100according to an embodiment of the instant invention. The stroller 100comprises a stroller chassis and an adjustable seat assembly, which isdetachably mountable to the stroller chassis in either a rear facing ora front facing orientation. The stroller chassis comprises three radialtubular branch structures, including an upper frame member assembly 102that extends to form a push handle 104, a front frame member assembly106 that supports laterally spaced-apart front wheels 108, and a middleframe member assembly 110 that supports laterally spaced-apart rearwheels 112. For improved clarity, the seat web material has been omittedin FIG. 1 a.

More particularly, the upper frame member assembly 102 comprises leftand right side laterally spaced-apart upper frame members, each having aforward end portion and a rearward end portion. The rearward end portionof each upper frame member has an open end, which is sized and orientedfor receiving one end of the push handle 104. Similarly, the front framemember assembly 106 comprises left and right side laterally spaced-apartfront frame members each having a forward end portion and a rearward endportion, one of the front wheels 108 being mounted to the forward endportion of each of the front frame members. Finally, the middle framemember assembly 110 comprises left and right side laterally spaced-apartmiddle frame members each having a forward end portion and a rearwardend portion, each rearward end portion being coupled to one of the rearwheels 112. In this context, the term “rearward end portions” denotesthe ends of the frame members that are directed toward the rear of thestroller 100 and the term “forward end portions” denotes the ends of theframe members that are directed toward the front of the stroller 100.Further, the “rear” of the stroller 100 is considered to be the end atwhich the rear wheels 112 are mounted, whilst the “front” of thestroller 100 is considered to be end at which the front wheels 108 aremounted. Additionally, the “left side” of the stroller and the “rightside” of the stroller are both defined from the perspective of anoperator standing at the rear of the stroller 100 and facing toward thefront of the stroller 100.

The front wheels 108 rotate freely about a vertical kingpin steeringaxis so that the stroller can be easily maneuvered—commonly known as a“caster” wheel. Each front wheel 108 is mounted via an axle to a frontwheel fork 114. In this way, the front wheels 108 are aligned laterallywith a respective one of the front frame members 106, such that thefront wheels 108 do not protrude outwardly along the sides of thestroller 100. Optionally, the front wheels 108 are removable so that thestroller can be made more compact for storage or transport purposes.Quick release mechanisms 116, one for each of the front wheels 108,facilitate removal of the front wheels without the need for tools.Further optionally, the front wheels 108 have a torsion spring or othersuitable suspension system (not shown) to provide isolation ofroad/surface disturbances for a more comfortable ride.

As is shown in FIGS. 1 c-1 e, the rear wheels 112 are detachablymountable to the stroller via quick release mechanisms. By way of aspecific and non-limiting example, each rear wheel 112 includes apush-button type quick release axle 113. The axles 113 may be insertedinto axle holes 115 that are located along the outer faces of each ofthe left side and right side middle frame members 110 for use in adetached-stroller mode, or the axles 113 may be inserted into axle holes115 that are located along the inner faces of each of the left side andright side middle frame members 110 for use in a coupled-stroller mode.As is shown in FIG. 1 e, optionally one rear wheel 112 is mountedadjacent to the inner face of one middle frame member 110 whilst theother rear wheel 112 is mounted adjacent to the outer face of the othermiddle frame member 110. Notably, when the rear wheels 112 are mountedadjacent to the outer faces of the left side and right side middle framemembers 110 they cooperate to form a relatively wide and stable base forsupporting the stroller 100. In the illustrated embodiment, the rearwheels 112 form a base that is wider than a maximum frame width of thestroller chassis when the rear wheels 112 are mounted on the outer facesof the middle frame members 110. In this configuration, the relativelywidely spaced rear wheels 112 prevent the stroller from beingexcessively tippy when the stroller 100 is operated in thedetached-stroller mode. As is discussed in greater detail below, whenthe rear wheels 112 are mounted on the inner faces of the left side andright side middle frame members 110 the lateral separation between thetwo rear wheels 112 is less than a lateral separation between the twofront wheels 108. The ability to mount the rear wheels 112 on the innerfaces of the middle frame members 110 results in a laterally compactcoupled-stroller configuration, and avoids the problem of the rear wheelof one stroller interfering with the rear wheel of another stroller whentwo or more strollers are coupled together in a side-by-side manner. Ofcourse, when only two strollers are coupled together then optionally therear wheels that are disposed on the coupled (facing) sides of each ofthe two strollers are required to be mounted to the inner faces of therespective middle frame members. Optionally, the rear wheels that aredisposed on the outward facing sides of the coupled strollers remainmounted to the outer faces of the respective middle frame members.Further optionally, a different quick-release mechanism is employed fordetachably mounting the rear wheels 112 to the stroller.

Referring again to FIG. 1 a, the upper frame member assembly 102, thefront frame member assembly 106 and the middle frame member assembly 110are coupled together via a pair of central hubs 120, which are disposedone each on opposite sides of the stroller chassis. The central hubs 120define a folding axis therebetween, about which folding axis the upperframe member assembly 102, the front frame member assembly 106 and themiddle frame member assembly 110 mutually pivot between a rollingconfiguration and a folded configuration.

A first mounting structure is defined on an outward facing surface ofone of the central hubs 120, and a second mounting structure that iscomplementary to the first mounting structure is defined on an outwardfacing surface of the other one of the central hubs 120. Only one of thefirst and second mounting structures on hubs 120 is shown in FIG. 1 a.Two identical or complementary strollers 100 can be coupled together ina side-by-side manner by aligning the complementary mounting structureson respective central hubs 120 of the two strollers, and then slidinglyengaging the complementary mounting structures until an interlocking fitis achieved. Additionally, a pair of upper hubs 122 is provided on theupper frame member 102, with the first mounting structure being definedon an outward facing surface of one of the upper hubs 122 and the secondmounting structure being defined on an outward facing surface of theother one of the upper hubs 122. Only one of the first and secondmounting structures on hubs 122 is shown in FIG. 1 a. The complementarymounting structures on respective upper hubs 122 of the two strollerscan be interlocked in the same manner as the complementary mountingstructures on the central hubs 120, thereby forming a second point ofattachment between the two strollers 100.

Optionally, more than two points of attachment are provided in whichcase additional hubs, and the mounting structures associated therewith,are provided along the opposite sides of the stroller 100. In theexample that is shown in FIG. 1 a, the mounting structure on the upperhubs 122 is smaller than the mounting structure on the central hubs 120,and the diameter of the upper hubs 122 is smaller than the diameter ofthe central hubs 120. Optionally, the size of the mounting structure andthe hub diameter is substantially the same for both the upper hubs 122and the central hubs 120. Further optionally, the mounting structure onthe upper hubs 122 is larger than the mounting structure on the centralhubs 120, and the diameter of the upper hubs 122 is larger than thediameter of the central hubs 120. Additionally, in the instant example“male” portions of the mounting structure are provided on one side ofthe stroller 100, specifically the right side of the stroller, whilst“female” portions of the mounting structure are provided on the otherside of the stroller 100, specifically the left side of the stroller.Optionally a “male” portion of the mounting structure is provided on theupper hub 122 along one side of the stroller and on the central hub 120along the other side of the stroller, etc.

In order to fold the stroller 100, fold handle 124 is rotated and liftedupward to release a not illustrated locking mechanism disposed in eachof the central hubs 120. Continuing to lift the fold handle 124 causesthe upper frame member assembly 102 and the front frame member assembly106 to rotate about the folding axis that is defined between the centralhubs 120, until all three frame member assemblies stack together in asequential arc concentric fashion. As is described in greater detailbelow, the upper frame member assembly 102 and the front frame memberassembly 106 are coupled together by a mechanism that is disposed withinthe central hubs 120, so that they move in unison. The locking mechanismsupports the weight of the stroller 100 when the stroller 100 is beingused in its rolling or unfolded configuration.

In the example that is shown in FIG. la and FIG. lb the seat assembly isprovided in the form of a foldable toddler seat. The foldable toddlerseat comprises an upper seat frame 150 and a lower seat frame 152, whichare pivotally connected one to the other via connector assembly 154.Outward facing surfaces of the connector assembly 154 on opposite sidesof the seat assembly have a mounting structure for engaging acomplementary mounting structure that is defined on inward facingsurfaces of each of the central hubs 120. During use, the seat assemblyis lowered toward the stroller chassis until the mounting structure ofthe seat assembly engages the mounting structure of the strollerchassis. The seat assembly locks into the stroller chassis in either afront facing orientation (shown) or a rear facing orientation (notshown).

Integrated into the upper seat frame 150 is toddler seat recline adjusthandle 156. Actuating the toddler seat recline adjust handle 156releases a mechanism in the connector assembly 154, which permits thetoddler seat to be moved into one of three supported inclinationpositions.

A toddler seat grab handle 158 is integrated into the lower seat frame152. Actuating the toddler seat grab handle 158 releases a mechanism inthe connector assembly 154 and allows the lower seat frame 152 to befolded in an upward direction toward the upper seat frame 150, afterwhich the toddler seat may be detached and lifted away from the strollerchassis.

A footrest or step 160 is also provided to allow a child to step up intothe stroller 100, or to prevent the child's feet from dragging on theground surface when sitting in the foldable toddler seat.

Optionally, the push handle 104 is telescopically adjustable to provideheight and setback adjustment for users of different heights. Forinstance, the push handle 104 is held in position by two cam clampmechanisms 118—one on each side of the handle 104. Optionally, the pushhandle 104 is covered with a soft foam material for comfort.

Optionally, the stroller 100 is equipped with a not illustrated canopysystem that provides protection to the child from sun or rain and thatis adjustable so that it can be fully retracted out of the way or fullydeployed to completely cover the child. Further optionally, the strolleris equipped with a not illustrated storage basket underneath the seatingarea. The storage basket is at least partially constructed from aflexible fabric material so that it collapses when the stroller isfolded.

Referring now to FIG. 1 b, shown is the stroller 100 with the seat webmaterial in position. The seat web material includes flexible sides 162that are fastened to and suspended from the upper seat frame 150 and thelower seat frame 152, and which supports a central seating surface 164.Optionally, the central seating surface 164 is reinforced with rigidsupport members such as for instance plastic or fiberboard inserts.Further optionally the central seating surface 164 is padded for thecomfort of the occupant and/or covered with a weather resistantmaterial.

Optionally, the seat assembly is provided in the form of a rear-facinginfant car seat or a bassinette. When two or more strollers are coupledtogether, different seat assembly types may be mounted in differentstrollers such that children of varying ages may be transported incomfort and safety. The infant car seat or the bassinette may be mountedto the stroller chassis in either a forward facing or a rearward facingorientation.

Referring now to FIGS. 2 a and 2 b, shown are enlarged views of theupper hubs 122 and central hubs 120, respectively. With reference toFIG. 2 a, the upper hub 122 a includes a raised flange 200 projectingfrom the outward facing surface 202 thereof. The raised flange has aninwardly beveled edge 204 around at least a portion of its periphery.The upper hub 122 b includes a slot 206 that is recessed below theoutward facing surface 208 thereof. The recessed slot 206 has anoutwardly beveled edge 210 around a portion of its periphery. When twostrollers 100 are coupled together, the hub 122 a of one stroller 100 isaligned with the hub 122 b of the other stroller (100′, see FIG. 3) andthe raised flange 200 is slidingly engaged in the recessed slot 206. Inorder to facilitate the interconnection of the flange 200 and the slot206, the flange 200 is convexly curved along a leading edge thereof in adirection of sliding engagement. The recessed slot 206 is shaped toaccommodate the convexly curved leading edge of the raised flange 200.Disposed within the recessed slot 206 is a releasable retainingmechanism or latch 212 for retaining the flange 200 and the slot 206 inan interconnected state. A not illustrated actuator releases theretaining mechanism 212 when the strollers are to be decoupled.

With reference to FIG. 2 b, the central hub 120 a includes a raisedflange 220 projecting from the outward facing surface 222 thereof. Theraised flange has an inwardly beveled edge 224 around at least a portionof its periphery. The central hub 120 b includes a slot 226 that isrecessed below the outward facing surface 228 thereof. The recessed slot226 has an outwardly beveled edge 230 around a portion of its periphery.When two strollers 100 are coupled together, the hub 120 a of onestroller 100 is aligned with the hub 120 b of the other stroller and theraised flange 220 is slidingly engaged in the recessed slot 226. Inorder to facilitate the interconnection of the flange 220 and the slot226, the flange 220 is convexly curved along a leading edge thereof in adirection of sliding engagement. The recessed slot 226 is shaped toaccommodate the convexly curved leading edge of the raised flange 220.Disposed within the recessed slot 226 is a releasable retainingmechanism or latch 232 for retaining the flange 220 and the slot 226 inan interconnected state. A not illustrated actuator releases theretaining mechanism 232 when the strollers are to be decoupled.

Referring now to FIG. 2 c, shown is a rear view of the upper hubs of twostrollers in a coupled condition. As is shown in FIG. 2 c, theprojecting flange 200 of one upper hub and the recessed slot 206 ofanother upper hub cooperate to form a “dove-tail” like connection, whenviewed from the rear of the stroller 100 along a direction toward thefront of the stroller 100. The central hubs interconnect one withanother in an analogous fashion. FIG. 2 c illustrates the laterallycompact nature of the mounting structure that is used to couple twostrollers 100 together. In particular, the thickness of two hubs whencoupled together is smaller than the sum of the thickness of the twohubs separately, including the associated mounting structure. Themounting structure that is shown in detail in FIGS. 2 a-2 c supportsvery close coupling together of two or more strollers, providing arelatively narrow structure when two or more strollers are coupled,which facilitates releasable use in urban environments where narrowdoorways, crowded aisles, etc. are expected to be encountered.Alternatively, the mounting structure that is shown in FIGS. 2 a-2 c israpidly decoupled, thereby allowing each of the two or more strollers tonavigate narrow or crowded spaces separately.

Referring now to FIG. 3, shown is a rear view of a first stroller 100and a second stroller 100′ coupled together, for operation in acoupled-stroller mode. In particular, the central hub 120 b and upperhub 122 b of stroller 100 are interconnected with the central hub 120 a′and upper hub 122 a′ of stroller 100′, respectively. As such, stroller100 and stroller 100′ are interconnected at two points of attachment.Also shown in FIG. 3 are the attachment of rear wheels 112 and 112′ tothe inner faces of middle frame members 110 and 110′, respectively.Thus, the rear wheel 112 on the right-hand side of stroller 100 isspaced apart from the rear wheel 112′ on the left-hand side of stroller100′, thereby avoiding mutual interference. At the same time, the widespacing between the rear wheel 112 on the left-hand side of stroller 100and the rear wheel 112′ on the right-hand side of stroller 100′ providesa stable base for the for the coupled-stroller mode. Also shown in FIG.3, each rear wheel 112 or 112′ includes a toothed hub 302 or 302′,respectively, which is disposed adjacent to the middle frame member 110or 110′, respectively, when the rear wheel 112 or 112′ is mountedthereto.

In the context of FIG. 3, and throughout the rest of this document, an“inner face” or an “inward facing surface” is considered to be the faceor surface of a stroller component that is directed toward a strollercenterline running along the length of the stroller. Thus, “inner faces”or “inward facing surfaces” of a stroller component typically face oneanother due to the approximate symmetry of the stroller componentsrelative to the stroller centerline. Similarly, an “outer face” or an“outward facing surface” is considered to be the face or surface of astroller component that is directed away from the stroller centerline.Thus, “outer faces” or “outward facing surfaces” of a stroller componentdo not face one another.

Referring now to FIGS. 4 a and 4 b, shown is a brake mechanism accordingto an embodiment of the instant invention. FIGS. 4 c and 4 dadditionally show a brake lever 123 and a control cable 400 for remotelyactuating the brake mechanism. As is shown most clearly in FIG. 4 a, oneend of the control cable 400 is connected to a first end of rocker arm402 at connection point 404. The other end of the control cable 400 isconnected to the brake lever 123, which is disposed on one of the upperhubs 122, as is shown most clearly in FIG. 4 d. Rocker arm 402 ispivotally mounted on a rocker pivot pin 406. A first end of a retainingrod 408 is pivotally coupled to a second end of the rocker arm 402 via aswivel seat 410, which is secured to the second end of the rocker arm402 by pin 412. A second end of the retaining rod 408 has a flange 414extending perpendicularly from the retaining rod 408. The second end ofthe retaining rod 408 is disposed within a lock-pin support member 416.The lock-pin support member has a passageway extending therethroughbetween first and second opposite ends thereof. A first portion of thepassageway 417 a that is proximate the first end is dimensioned smallerthan the retaining rod flange 414, and a second portion of thepassageway 417 b that is proximate the second end is dimensioned largerthan the retaining rod flange 414. A transition between the firstportion of the passageway 417 a and the second portion of the passageway417 b defines an interior bearing-surface 418. As is shown most clearlyin FIG. 4 b, the retaining rod flange 414 faces the interiorbearing-surface 418 and acts to limit the travel of the lock-pin supportmember 416 in a direction away from the rocker arm. A lock-pin 428 ismounted perpendicularly to the lock-pin support member 416 proximate thesecond end thereof. The lock-pin 428 extends in first and secondopposite directions, into and out of the plane of the page in FIG. 4 b,from the lock-pin support member 416.

The swivel seat 410 includes a flange 420 against which a first end of afirst resilient member 422 is retained. A second end of the firstresilient member 422 is retained against a first side of a stop 424. Inaddition, a second resilient member 426 is disposed between a secondside of the stop 424 and the first end of the lock-pin support member416. In the instant example, the first resilient member 422 and thesecond resilient member 426 are both compression springs. As is shown inFIG. 4 a and FIG. 4 b, the brake mechanism components are at leastpartially enclosed by a housing 430. In the instant example, the stop424 is integrally formed with the housing 430.

When the control cable 400 is pulled by the action of rotating the brakelever 123, the rocker arm 402 is caused to pivot about rocker pivot pin406. As the rocker arm 402 pivots, the first resilient member 422 iscompressed against stop 424 and the retaining rod 408 moves in adirection toward the toothed hub 302. The second resilient member 426pushes the lock-pin support member 416 along the direction of movementof the retaining rod 408, thereby moving the lock-pin 428 into aretaining groove between two adjacent teeth of the toothed hub 302.

When the brake lever 123 is lifted by an operator past a locking detentposition, the first resilient member 422 forces the rocker arm back intoa driving position, thereby compressing the second resilient member 426and causing the retaining rod 408 and the lock-pin support member 416 tomove in a direction away from the toothed hub 302, so as to remove thelock-pin 428 from the retaining groove between two adjacent teeth of thetoothed hub.

The components of the brake mechanism are mounted to the middle framemember 110 in such a way as to provide braking functionality when therear wheels 112 of stroller 100 are mounted adjacent to either the innerfaces or the outer faces of the middle frame member assembly 110. Inparticular, the lock-pin 428 is mounted perpendicular to the lock-pinsupport member 416 and extends both into and out of the plane of thepage in FIG. 4 b. Extending into the plane of the page, the lock-pin 428passes through a slot 432 in middle frame member 110, and protrudesthrough to the opposite side of middle frame member 110. During use, thelock-pin 428 travels within the slot 432. Extending out of the page, thelock-pin 428 passes through a not illustrated slot in a not illustratedhousing member that is secured over the brake mechanism components whenin an assembled condition. Thus, the lock-pin 428 protrudes away fromboth the inner and outer faces of the middle frame member 110, such thatlock-pin 428 is capable of engaging the toothed hub 302 when the rearwheel 112 is mounted adjacent to either the inner face or the outer faceof the middle frame member 110. Additionally, a not illustrated torquetube is aligned with the rocker pivot pin 406 for transmitting motion toa second rocker arm of a second brake assembly that is mounted to themiddle frame member 110 on the opposite side of the stroller.Accordingly, by rotating a single brake lever 123 an operator is able toactuate simultaneously the brake mechanisms adjacent to each one of therear wheels 112 of stroller 100.

Referring again to FIGS. 4 c and 4 d, the brake lever 123 is disposed onthe inward facing surface of one of the upper hubs 122, which in thiscase is the right-hand side upper hub. The brake lever 123 ishand-actuatable, and is in communication with the above-mentioned brakemechanisms disposed near the rear wheels 112 via the control cable 400,which extends along the upper frame member 102 from the upper hub 122 tothe central hub 120, and along the middle frame member 110 from thecentral hub 120 to a brake mechanism. Clips 434 are used to secure thecontrol cable 400 to the frame members 102 and 110. When the brake lever123 is rotated downward by a predetermined amount, a locking detent isengaged to hold the brake lever 123 in a braking position. The action ofrotating the lever pulls on the cable 400, to remotely activate thebrake mechanism.

Referring now to FIG. 5 a, shown is a folding mechanism according to anembodiment of the instant invention. In particular, the foldingmechanism is shown in FIG. 5 a in a rolling or unfolded condition. Thefolding mechanism includes a first rotatable member 500, and a secondrotatable member 502. The first rotatable member 500 has a generallypie-wedge shaped, flat plate portion with an aperture disposed proximatethe vertex thereof, and an elongated arm for attachment to front framemember 106. Similarly, the second rotatable member 502 has a generallypie-wedge shaped, flat plate portion with an aperture disposed proximatethe vertex thereof and an elongated arm for attachment to the upperframe member 102. For each of the first and second rotatable members 500and 502, the flat plate portions and the elongated arms are depicted asbeing formed of a single flat piece; however, in other implementationsthe flat plate portions and the elongated arms are optionally individualpieces that are fixedly attached together.

The first and second rotatable members 500 and 502 are contained betweeninner and outer slotted halves of a housing, hub 120, allowing theelongated arms to protrude outside of the housing. Also contained withinthe housing is a linkage assembly, including a linkage pin 508, a firstlinkage arm 510, and a second linkage arm 512. A first end of the firstlinkage arm 510 is pivotally coupled to the first rotatable member 500via pin 524. Similarly, a first end of the second linkage arm 512 ispivotally coupled to the second rotatable member 502 via pin 526.Linkage pin 508 couples together a second end of the first linkage arm510 and a second end of the second linkage arm 512. Additionally, theinside wall of at least one of the inner half and the outer half of thehousing has a slot or guide-channel 506, which is sized and shaped toreceive the linkage pin 508. The first and second rotatable members 500and 502 are coupled to the linkage pin 508, and thus to one another, viathe first and second linkage arms 510 and 512 and the linkage pin 508.During operation, the linkage pin 508 slidingly travels within theguide-channel 506, such that the first rotatable member 500 and thesecond rotatable member 502 rotate relative to each other in asynchronized fashion when the foldable stroller is converted between arolling configuration and a folded configuration.

The apertures of the first and second rotatable members are sized toreceive a bushing 514 therethrough, the bushing 514 having a length thatis longer than the cumulative thickness of the two rotatable members.The first and second rotatable members are rotatably mounted on thebushing for rotation in parallel rotation planes about an axis ofrotation transverse to the plane of the flat plate portions. The endportions of the bushing extend beyond the apertures, and have acircumferential groove to receive a C-clip to retain the bushing inplace. The bushing also extends through a not illustrated washerdisposed between the flat plate portions of the first and secondrotatable members 500 and 502, respectively, to serve as a spacer andbearing surface for rotational movement of the rotatable members aboutthe bushing.

The first rotatable member 500 and the second rotatable member 502 eachhas a notch defined along the perimeter thereof, at respective locationsfor receiving lock-pin 504 when the stroller is in the rolling, orunfolded, configuration. The lock-pin 504 is carried by a sliding block516, which is normally biased toward the first and second rotatablemembers 500 and 502 by spring 518. A cable 520 extends through themiddle frame member 110 between the fold handle 124 and sliding support522. When the fold handle 124 is lifted upwards, a cable hook 528rotates and causes the cable 520 to pull the sliding block 516 andcompress the spring 518. As sliding block 516 continues to move in adirection to compress the spring 518, lock-pin 504 is withdrawn from thenotches in the first and second rotatable members 500 and 502, so as torelease the locking mechanism that prevents stroller folding.

When the fold handle 124 is lifted and the lock-pin 504 is withdrawnfrom the locking position, the first and second rotatable members 500and 502 pivot about bushing 514 as the upper frame member assembly 102and the front frame member assembly 106 begin to move downward under theinfluence of gravity. The first and second rotatable members 500 and 502are coupled together via the first and second linkage arms 510 and 512and the linkage pin 508. The linkage pin 508 travels along guide-channel506 as the first and second rotatable members 500 and 502 pivot towardthe folded condition. As a result, the interconnected first and secondrotatable members 500 and 502 pivot in unison as the stroller 100 isconverted between the rolling configuration and the foldedconfiguration.

FIG. 5 b shows a portion of FIG. 5 a that is within the dashed-linesquare. In particular, FIG. 5 b omits the sliding block 516 so as toshow more clearly the lock-pin 504 seated within the notches that aredefined in the first and second rotatable members 500 and 502. Since thefirst and second rotatable members 500 and 502 overlap substantially,only the notch 602 that is defined in the second rotatable member 502 isvisible in FIG. 5 b.

Referring now to FIG. 5 c, shown is the mechanism of FIG. 5 a in afolded configuration. FIG. 5 c shows more clearly that the firstrotatable member 500 has a notch 600 and that the second rotatablemember 502 has a notch 602. In the rolling configuration that is shownin FIG. 5 a, the notch 600 and the notch 602 are aligned one with theother and retain the lock pin 504, thereby supporting the weight ofstroller 100 and preventing folding of the same.

The folding mechanism that is shown in FIGS. 5 a-5 c is laterallycompact and reduces the number of moving parts compared to knownstroller folding mechanisms.

FIGS. 6 a-6 c are side views of the stroller chassis in: a rollingconfiguration; in a partially folded configuration; and, in a fullyfolded configuration, respectively. When the stroller chassis ispartially folded, as is shown in FIG. 6 b, the fold handle 124 issubstantially vertical. A user may lift the stroller by the grab handle124, which in turn causes the stroller to continue to collapse under theinfluence of gravity.

Referring now to FIG. 7 a, shown is an enlarged partial view of thestructure for mounting the seat assembly to the stroller chassis. Asshown in FIG. 7 a, the inward facing surface 700 of hub 120 has amounting structure 702, in the form of a “D-shaped” pin, which projectstherefrom. Additionally, a rack 704 comprising a series of lockinggrooves is defined within a raised section of the inward facing surface700, along a portion of the perimeter of hub 120 that is approximatelycentered about the middle frame member 110. The connector assembly 154has a smooth inward facing surface 706, for the safety of the occupantof stroller 100. In addition, the outward facing surface 708 of theconnector assembly 154 has a mounting structure 710, in the form of asubstantially keyhole shaped groove, which is complementary to themounting structure 702.

Referring now to FIG. 7 b, shown is a plan view of the mountingstructure on the inner surface of the coupling assembly 154 of the seatassembly. In particular, the substantially keyhole shaped groove of themounting structure 710 is defined by a recessed slot having a narrowslot portion 710 b disposed between two relatively wider slot portions710 a and 710 c. The width “d1” of the narrow portion 710 b issubstantially equal to the separation between the two mutually parallelsides of the shaft 714.

Referring now to FIG. 7 c, shown is a side view of the mountingstructure on the inward facing surface 700 of hub 120. The mountingstructure 702 comprises a shaft 714 projecting from the inward facingsurface 700. The shaft 714 has two mutually parallel flat sides, whichare joined by opposite convexly curved sides. Optionally, the shaft 714has a not illustrated flange at the distal end thereof, relative to thesurface 700, projecting perpendicularly from the shaft 714.

FIGS. 7 d and 7 e show a top view and a side view, respectively, of themounting structure on the inward facing surface 700 of hub 120. Thedistance “d1” between the two mutually parallel sides of shaft 714 issmaller than the distance “d2” between opposite centers of the convexlycurved sides joining the two mutually parallel sides of shaft 714.

When the seat assembly is to be mounted in the stroller chassis, themounting structures 710 on either side of the seat assembly are alignedwith the corresponding mounting structures 702 on the stroller chassis.The shaft 714 must be aligned so that the two mutually parallel sidesthereof fit through the narrow portion 710 b of the mounting structure710. Once aligned properly, the shaft 714 of mounting structure 702 isurged into the wider portion 710 c of the mounting structure 710, andthe seat assembly is unfolded. Unfolding the seat assembly causes thecoupling assembly 154 to rotate, such that the two mutually parallelsides of shaft 714 no longer line up with the narrow portion 710 b ofmounting structure 710. Thus, the unfolded seat assembly cannot lift offthe stroller chassis. In particular, the seat assembly must be foldedand rotated into an approximately vertical orientation in order tore-align the two mutually parallel sides of shaft 714 with the narrowportion 710 b of mounting structure 710, after which the seat assemblymay be lifted off the stroller chassis.

Referring now to FIG. 8 a and FIG. 8 b, shown is an enlarged partialview of the seat inclination mechanism. The upper seat frame 150 andlower seat frame 152 are pivotally connected via pin 800 of theconnector assembly 154. The rocker member 806 pivots about pin 808, andis connected to cable 810, pawl 812 and spring 814. The pawl 812 has twoprojections 816 a and 816 b for interlocking with two adjacent lockinggrooves of the rack 704. Spring 814 normally biases the projections 816a and 816 b of pawl 812 into engagement with rack 704, such thatinclination of the seat assembly relative to the stroller chassis isprevented.

To adjust inclination of the seat assembly relative to the strollerchassis a hand actuated mechanism, toddler seat recline adjust handle156, is squeezed to pull on cable 810, thereby causing rocker member 806to pivot about pin 808 and to move the projections 816 a and 816 b ofpawl 812 out of contact with the locking grooves of rack 704. Once theprojections 816 a and 816 b are completely clear of the rack, thetoddler seat inclination may be adjusted. Once the adjustment iscomplete, release trigger latch 802 and spring 814 returns the rockermember 806 to its original position, such that projections 816 a and 816b engage two different locking grooves of rack 704. The seat assembly isthen locked in the new inclination position.

Referring now to FIGS. 9 a-9 c, shown is the toddler seat assembly in aninclined-forward position, a normal position, and a reclined position,respectively. FIGS. 9 d-9 f show the seat inclination mechanism in eachof the inclined-forward position, the normal position, and the reclinedposition, respectively. In FIG. 9 d the projections 816 a and 816 b ofpawl 812 engage the two most rearward locking grooves of rack 704,thereby locking the seat assembly in the inclined-forward position. InFIG. 9 e the projections 816 a and 816 b of pawl 812 engage the twocentral locking grooves of rack 704, thereby locking the seat assemblyin the normal position. Finally, in FIG. 9 f the projections 816 a and816 b of pawl 812 engage the two most forward locking grooves of rack704, thereby locking the seat assembly in the reclined position.

Referring now to FIG. 10, shown is an enlarged partial perspective viewshowing the upper hub 122 and an accessory having a mounting structurefor coupling to the upper hub 122. In the instant example the accessoryis shown in the form of a cup holder 1000. Optionally, other accessoriesmay be substituted for the cup holder, such as for instance a shoppingbag hook or a closable pouch for holding keys, change, a cell phone,glasses, etc. Optionally, a not illustrated adapter is provided in theform of a flat disk having on opposite sides thereof the same mountingstructure that is shown on the hub 122 of FIG. 10. The adapter allows,by way of a specific and non-limiting example, a second cup holder 1000to be mounted to the hub 122 on the opposite side of stroller 100.Optionally, the not illustrated adapted is used to mount a differentaccessory to the hub 122 on the opposite side of stroller 100.

Referring now to FIG. 11, shown is a perspective view showing anaccessory in the form of a tray 1100 mounted to stroller 100, andanother accessory in the form of a cup holder 1000 mounted to one of theupper hubs 122. In particular, the tray 1000 has first and secondmounting structures positioned for coupling to the central hubs 120 ofstroller 100. The first and second mounting structures are substantiallythe same as described above for he upper hub.

Optionally, an infant car seat assembly is used for newborn infants(0-12 months) and can be installed onto the stroller chassis in lieu ofthe foldable toddler seat that is shown in FIG. 1 b. In particular, theinfant car seat is mountable in both a forward and a rearward facingposition, but is not adjustable for different recline positions. The carseat must be removed from the stroller chassis in order to fold thestroller. This would typically occur when travelling by car where theinfant car seat would be removed from the stroller and installed intothe vehicle while the stroller chassis would be stored in the trunk.Further optionally, a bassinette is used for newborn infants (0-8months) and can be installed onto the stroller chassis in lieu of thetoddler seat or the infant car seat. In particular, the bassinette ismountable in both a forward and a rearward facing position, but is notadjustable for different recline positions so that the surface on whichthe child lays remains horizontal at all times. The bassinette isfoldable so that it can be folded along with the stroller chassis forcompact storage and transport.

Numerous other embodiments may be envisaged without departing from thescope of the instant invention.

1. A stroller, comprising: left and right front wheels; left and rightside laterally spaced-apart front frame members, each of the left andright side front frame members having a forward end portion and arearward end portion, the forward end portion of the left side frontframe member being coupled to the left front wheel and the forward endportion of the right side front frame member being coupled to the rightfront wheel; left and right rear wheels; left and right side laterallyspaced-apart middle frame members, each of the left and right sidemiddle frame members having a forward end portion and a rearward endportion, the rearward end portion of the left side middle frame memberincluding a wheel mounting structure along an outer face thereof andalong an inner face thereof opposite the outer face, the rearward endportion of the right side middle frame member including a wheel mountingstructure along an outer face thereof and along a inner face thereofopposite the outer face, so that the left rear wheel is selectablymountable adjacent to either the outer face or the inner face of theleft side middle frame member, and so that the right rear wheel isselectably mountable adjacent to either the outer face or the inner faceof the right side middle frame member; left and right side laterallyspaced-apart upper frame members, each of the left and right side upperframe members having a forward end portion and a rearward end portion;and, left and right side laterally spaced apart hubs disposed betweenand interconnecting corresponding ones of the front, middle and upperframe members, the left and right side hubs having complementary halvesof an interlocking mounting structure defined on outward facing surfacesthereof, wherein side-by-side coupling of two strollers is supported byinterlocking one of the left and right side hubs of one of the twostrollers with the other one of the left and right side hubs of theother one of the two strollers.
 2. The stroller according to claim 1,wherein a lateral separation between the complementary halves of theinterlocking mounting structure defined on the outward facing surfacesof the left and right side hubs defines a maximum frame width of thestroller.
 3. The stroller according to claim 2, wherein a lateralseparation between the left and right rear wheels is greater than themaximum frame width of the stroller when the left and right rear wheelsare mounted adjacent to the outer faces of the left and right middleframe members, respectively, and wherein a lateral separation betweenthe left and right rear wheels is less than the maximum frame width ofthe stroller when the left and right rear wheels are mounted adjacent tothe inner faces of the left and right middle frame members,respectively.
 4. The stroller according to claim 1, wherein the left andright rear wheels each comprise a quick release axle and wherein thewheel mounting structure on the inner and outer faces of the left andright middle frame members comprises an axle hole for receiving thequick release axle of a respective one of the left and right rearwheels.
 5. The stroller according to claim 1, wherein the complementaryhalves of the interlocking mounting structure comprises a raised flangestructure disposed on one of the left and right side hubs and a recessedslot structure disposed on the other one of the left and right sidehubs.
 6. The stroller according to claim 1, comprising left and rightlaterally spaced apart upper hubs disposed one each along an outer faceof the left and right upper frame members, respectively, the left andright upper hubs having complementary halves of an interlocking mountingstructure defined on outward facing surfaces thereof, wherein a secondpoint of attachment between two coupled strollers is provided byengaging facing ones of the left and right upper hubs of the two coupledstrollers.
 7. The stroller according to claim 1, wherein the twostrollers comprise at least one of a toddler seat frame, an infant carseat, and a bassinette.
 8. A stroller, comprising: a front frame memberassembly supporting a pair of laterally spaced apart front wheels; amiddle frame member assembly supporting a pair of laterally spaced apartrear wheels, the middle frame member assembly configured so that therear wheels are detachably mountable one each adjacent to outer faces ofthe middle frame member assembly for operation in a detached operatingcondition between a first and a second stroller, and so that the rearwheels are detachably mountable one each adjacent to inner faces of themiddle frame member assembly for operation in a coupled operatingcondition between a first and a second stroller; an upper frame memberassembly with a push handle portion; first and second laterally spacedapart hubs disposed between and interconnecting the front frame memberassembly, the middle frame member assembly, and the upper frame memberassembly, the first hub having a first mounting structure defined on anoutward facing surface thereof and the second hub having a secondmounting structure defined on an outward facing surface thereof, thesecond mounting structure different than the first mounting structure,the first and second mounting structures defining complementary halvesof a first interlocking coupling mechanism; wherein the first mountingstructure disposed on the outward facing surface of the first hub of thefirst stroller is aligned with and engages the second mounting structureon the outward facing surface of the second hub of the second stroller,for detachably securing the first stroller to the second stroller in aside-by-side fashion.
 9. The stroller of claim 8, comprising third andfourth laterally spaced apart hubs disposed on the upper frame memberassembly, the third hub having a third mounting structure defined on anoutward facing surface thereof and the fourth hub having a fourthmounting structure defined on an outward facing surface thereof, thefourth mounting structure different than the third mounting structure,the third and fourth mounting structures defining complementary halvesof a second interlocking coupling mechanism, wherein the third mountingstructure on the outward facing surface of the third hub of the firststroller is aligned with and engages the fourth mounting structure onthe outward facing surface of the fourth hub of the second stroller whenthe first stroller and the second stroller are detachably secured in theside-by-side fashion.
 10. The stroller according to claim 8, wherein alateral separation between the first mounting structure that is definedon the outward facing surface the first hub and the second mountingstructure that is defined on the outward facing surface of the secondhub defines a maximum frame width of the stroller.
 11. The strolleraccording to claim 10, wherein a lateral separation between the rearwheels is greater than the maximum frame width of the stroller when therear wheels are detachably mounted one each adjacent to the outer facesof the middle frame member assembly, and wherein a lateral separationbetween the rear wheels is less than the maximum frame width of thestroller when the rear wheels are detachably mounted one each adjacentto the inner faces of the middle frame member assembly.
 12. The strolleraccording to claim 1, wherein each one of the rear wheels comprises aquick release axle, and wherein the middle frame member comprises anaxle hole along each inner face thereof for receiving the quick releaseaxles when in the coupled operating condition, and wherein the middleframe member comprises an axle hole along each outer face thereof forreceiving the quick release axles when in the detached operatingcondition.
 13. The stroller according to claim 9, wherein one of thefirst and second mounting structures comprises a raised flange and theother one of the first and second mounting structures comprises arecessed slot, and wherein one of the third and fourth mountingstructures comprises a raised flange and the other one of the third andfourth mounting structures comprises a recessed slot.
 14. A stroller,comprising: a front frame member assembly supporting a pair of laterallyspaced apart front wheels; a middle frame member assembly supporting apair of laterally spaced apart rear wheels, the middle frame memberassembly including first and second wheel mounting structures disposedalong outer faces thereof on opposite sides of the stroller andincluding third and fourth wheel mounting structures disposed alonginner faces thereof on opposite sides of the stroller, so that the pairof rear wheels is selectably mountable adjacent to either the outerfaces or the inner faces of the middle frame member, a lateralseparation between the pair of rear wheels being greater when the pairof rear wheels is mounted adjacent to the outer faces of the middleframe member relative to when the pair of rear wheels is mountedadjacent to the inner faces of the middle frame member; an upper framemember assembly extending to a push handle end; a first hub disposed ona first side of the stroller and a second hub disposed on a second sideof the stroller and opposite the first hub, the first and second hubsdisposed between and interconnecting the front frame member assembly,the middle frame member assembly, and the upper frame member assembly,the first hub having a raised flange portion of a first interlockingcoupling mechanism defined on an outward facing surface thereof and thesecond hub having a recessed slot portion of the first interlockingcoupling mechanism defined on an outward facing surface thereof; a thirdhub disposed on the first side of the stroller and proximate the pushhandle end of the upper frame member assembly and a fourth hub disposedon the second side of the stroller and proximate the push handle end ofthe upper frame member assembly, the third hub having one of a raisedflange portion and a recessed slot portion of a second interlockingcoupling mechanism defined on an outward facing surface thereof and thefourth hub having the other one of the raised flange portion and therecessed slot portion of the second interlocking coupling mechanismdefined on an outward facing surface thereof; wherein for coupling thestroller with a second stroller, the raised flange portion of the firsthub on the first side of the stroller slidingly engages the recessedslot portion of the second hub on the second side of the secondstroller, and the one of the raised flange portion and the recessed slotportion of the third hub on the first side of the stroller slidingengages the other one of the raised flange portion and the recessed slotportion on the fourth hub on the second side of the second stroller. 15.The stroller according to claim 14, wherein each one of the rear wheelscomprises a quick release axle.
 16. The stroller according to claim 15,wherein the first and second wheel mounting structures each comprise anaxle hole for receiving the quick release axle of one rear wheel of thepair of rear wheels, so as to support a detached operating mode of thestroller in which the pair of rear wheels is mounted adjacent to theoutside faces of the middle frame member assembly.
 17. The strolleraccording to claim 15, wherein the third and fourth wheel mountingstructures each comprise an axle hole for receiving the quick releaseaxle of one rear wheel of the pair of rear wheels, so as to support acoupled operating mode of the stroller in which the pair of rear wheelsis mounted adjacent to the inside faces of the middle frame memberassembly.
 18. A method comprising: providing a first stroller and asecond stroller each comprising a frame supported by a pair of laterallyspaced apart front wheels and a pair of laterally spaced apart rearwheels, the frame of each stroller comprising first and second mountingstructures on a first side thereof and comprising third and fourthmounting structures on a second side thereof, the second side oppositethe first side of the stroller, a maximum frame width being definedbetween outward facing surfaces of the first and third mountingstructures, each one of the pair of laterally spaced apart rear wheelsbeing detachably mounted adjacent to an outer face of a rear-wheelsupport member on opposite sides of the frame, such that a lateralseparation between the rear wheels is greater than the maximum framewidth; detaching each rear wheel from a respective rear-wheel supportmember on each one of the first stroller and the second stroller;detachably mounting each rear wheel to an inner face of a respectiverear-wheel support member on opposite sides of the frame of each one ofthe first stroller and the second stroller, such that for each one ofthe first stroller and the second stroller the rear wheels are laterallyspaced apart by an amount that is less than the maximum frame width ofthe respective stroller; and, detachably engaging the first and secondmounting structures on the first side of the frame of the first strollerwith the third and fourth mounting structures on the second side of theframe of the second stroller, respectively, so as to couple the firststroller with the second stroller in a side-by-side fashion with twopoints of attachment, wherein a maximum overall width of the first andsecond stroller, when coupled together in the side-by-side fashion, doesnot exceed the sum of the maximum frame width of the first stroller andthe maximum frame width of the second stroller.
 19. The method accordingto claim 18, wherein detaching each rear wheel from a respectiverear-wheel support member comprises activating a quick release mechanismof each rear wheel.
 20. The method according to claim 18, wherein eachrear wheel comprises a quick release axle, and wherein detachablymounting each rear wheel to an inner face of a respective rear-wheelsupport member comprises engaging the quick release axle of each rearwheel within an axle hole that is defined along the inner face of therespective rear-wheel support member.